This invention relates generally to hot fluid generators and in particular to steam generators for the recovery of liquefiable minerals from subterranean formations.
Apparatus for the sucessful recovery of minerals using a high pressure thermal vapor stream typically involves the production of hot combustion gases for flow into a steam generating device for producing sufficient quantities of high pressure thermal vapor of steam and combustion gases which are injected into the subsurface formation for economical recovery of highly viscous petroleum therefrom. Examples of some such apparatus are described in the following U.S. Pat. Nos. to name a few: 3,980,137; 3,620,571; 2,916,877; 2,839,141; 2,793,497; 2,823,752; 2,734,578; 2,754,098; and Mexican Pat. Nos. 105,472 and 106,801. Certain very viscous hydrocarbon deposits need large amounts of heat applied thereto to reduce the viscosity to make possible recovery. Because of the very large amounts of heat that are generated and required, difficulties arise in protecting the combustion chambers of thermal vapor generators from overheating while still having the capability of providing sufficient heat of formation to effect oil recovery.